Twist-tie bag closing machine

ABSTRACT

A machine for closing the open, gathered ends of flexible bags, such as bags of paper or plastic, incorporates a plurality of air operated cylinders which serve to carry out the various functions of feeding a length of tying tape into position, cutting off the desired length of tape, driving a forming arm to form the tape about the neck of the bag, and activating the rotating hooked twister for twisting the ends of the tying tape together.

United States Patent" 91 v Crabb July 23, 1974 [54] TWIST-TIE BAG CLOSING MACHINE 3,721,061 3/1973 Bodolay 140/93 A In e o Jaspe R Crabb, Yakima wash. 3,731,454 5/1973 Crabb 53/198 A X Assigneel Dflmain Industries, e Primary ExaminerCharles w. Lanham Rlchmond, Assistant Examiner-E. M. Combs [22] Filed: June 5 1972 Attorney, Agent, or FirmH. Dale Palmatier; James R. Haller [21] Appl. No.: 259,834

[57] ABSTRACT 5 140/93 A machine for closing the open, gathered ends of flex- [58] Field of s e ir c ii ilo/93A 113 5.3/138 A bags as brags F P135119 l g A 198 rates a plurality of air operated cylinders which serve to carry out the various functions of feeding a length [56] References Cited of tying tape into position, cutting off the desired length of tape, driving a forming arm to form the tape UNITED STATES PATENTS about the neck'of the bag, and activating the rotating 1,293,267 2/1919 Warwick /93 A hooked twister for twisting the ends of the tying tape 3,126,684 3/1964 Bower 53/198 A t th 3,276,235 10/1966 Stanley 72/149 3,538,960 11/1970 Tetrick 140/93 A 5 Claims, 5 Drawing Figures 88 98 108 150 146 4 22 m a 111..., A; u i 48 I 486 zo 14 n 23F?! 100 126 v @/12@@ mm 114 E5 1 l 120, 116 -50 56 5 I, ra g ll ll 18 z 81 1 1|- Lilli 28 58 a 5 0 o MEQEEI 1 TWIST-TIE BAG CLOSING MACHINE Packaging machines for gathering the ends of flexible bags together and twisting a flexible tie tape about the neck of the bag are in wide spread useparticularly in production line type of operations. Such devices are generally machine fed and the entire operation is automatic. Such devices are, of course, complicated and expensive.

In U.S. Pat. No. 3,538,960 is disclosed a small, twisttying machine particularly designed for use in smaller operations wherein the device requires an operator to manually feed the open end of the bag to the device. The device of said U.S. Pat. No. 3,538,960 has proved to be commercially successful and comprises a number of pivoted and moving levers operated by a rotating cam plate.

The present invention is of the type wherein an oper ator feeds individual bags to the device, as contrasted with the more automatic operation of assembly line production.

The present device is simplified in that it incorporates merely a plurality of air operated cylinders which are less subject to wear than lever and cam arrangements and reducing the number of moving parts still further. In addition, the air operation of the device permits use of compressed air already installed in a number of these establishments thus reducing cost since separate power means such as electric motors need not be utilized.

These and other objects and advantages will be aparent to those skilled in the art from the following specification and drawings in which:

FIG. 1 shows a top plan view of the device of the invention with the top cover broken away,

FIG. 2 shows a bottom plan view of the device,

FIG. 3 is an enlargement taken along the line 33 of FIG. 1,

FIG. 4 is an enlarged view showing the tape-tie as it is being twisted about the bag neck by the rotating twister, and

FIG. 5 is a cross-sectional view taken along lines 5-5 of FIG. 1.

The bag tying apparatus of this invention is shown in FIG. 1 as being mounted upon the plate having a generally V-shaped entranceway or notch 12 at its forward end. The device comprises 3 basic operating groups including a forming arm and tape-tie cut off arm generally indicated at 14, a tape-tie feeding mechanism generally indicated at 16, and a tape twisting mechanism generally indicated at 18. Each of the three operating sub-groups l4, l6, and 18 are operated by separate air cylinders 20, 22, and 24 respectively.

When an operator inserts the open upper end of a flexible bag into the throat 12 at the forward end of the device it strikes against a trigger arm 26 pivoted at 28 and moves the arm clockwise (as viewed in FIG. 1) against the urging of the spring 30. This clockwise movement of the arm 26 causes the opposite end 32 of the arm to operate an air valve (not shown) positioned beneath the securing plate 34. The extending accuating arm 36 of the air valve is operated by engagement with the end 32 of the lever 26. When the lever 26 operates the accuating lever 36 for the air. valve the cylinder (see FIG. 2) will be operated to extend its pistonrod 38 to the position shown in FIG. 2. The rod 38 is connected through floating pivot 40 to a link 42 the other end of which is fixed to the shaft 44 extending upwardly through the plate 10. As shown in FIG. 1 the shaft 44 has affixed thereto on the upper side of the plate 10 a bag forming and tie-tape cut off arm 46. Upon accuation of the air cylinder 20 by its air valve and the associated accuating lever 36 the forming arm 46 on the upper surface of the plate 10 will be .moved to its dotted line position transverse to the general direction of the throat 12. That is to say that the dotted line position of the forming arm 46 as shown in FIG. 1 corresponds to the extended position of the piston rod 38 as shown in FIG. 2.

As the forming arm 46 moves from its solid line position to its dotted line position as shown in FIG. I the gathering throat 48 thereof gathers the top open end of the flexible bag into the shape generally shown in FIG. 3 and at the same time loops or bends the tie-tape 50 about the neck of the gathered end of the bag. By the time the arm 46 has reached its full dotted line position as shown in FIG. 1 the tape 50 will be cutoff by means of the knife blade 52 fixed to the top surface of the plate 10 as it cooperates with the knife block 54 adjacent the slot 5.6 on the forming arm 46.

When the forming arm 46 is fully moved to its dotted line position as shown in FIG. 1 the pivoted lever 58 will be operated to activate valve 60 thus operating air cylinder 24. As shown in FIG. 2 operation of air cylinder 24 by means of the air valve 60 will retract the piston rod 62 from its extended position as shown in FIG. 2. Connected to the end of piston rod 62 is a chain 64 trained about a sprocket 66 and connected at its other end 68 to a spring 70. The spring 70 is fixed at 72 to a fixed portion of the frame of the machine. The sprocket 66 is fixed to a shaft 74 extending through the plate 10. On the upper surface of the plate 10 shaft 74 has affixed thereto a gear 76 in mesh with a gear 78 fixed to a shaft 80 journaled in suitable bearings 81 fixed to the plate 10. At its opposite end the shaft 80 has affixed thereto the twisting head 82 best shown in FIGS. 3 and 4. On its forward end the twisting head 82 fixed to the shaft 80 comprises a pair of oppositely extending arms 84 the blunt ends 86 of which are bent slightly forward to engage the loose ends of the tape-tie 50. Uponaccuation of the cylinder 24 and retraction of its piston rod 62 and the sprocket 66 will be rotated thus rotating shaft 74 gears 76 and 78 and shaft 80. This action will result in rotation of the twister head 82 having the twister arms 84 thereon.

At the instant the twister arms 86 start to revolve, the tape 50 is urged against the gathered bag neck by the forming arm 46 which engages the tape and bag neck at the deepest portion of the throat 48. The ends of the tape 50 respectively extend into openings 51 and 124 of the forming arm. The side lobes 48a of the throat 48 are opposite the twister arms 84, substantially as illustrated in the dotted line position of forming arm 46 in FIG. 1. In this position, the twister arms, as they begin to revolve with shaft 80, cannot miss the ribbon which forms a bight around the back neck and into the openings 51 and 124 of the forming arm. As the hook or twister arm 84 grabs the ribbon, the ribbon is bent on the back side of the hook, substantially as illustrated in FIG. 3, and the ends of the ribbon start moving out of the openings 51 and 124, but sufficient resistance is provided so that a very tight tie is made on the bag neck. The heart shape of the throat 48 in the forming arm 46 allows the twister arm or hook to twist within ence with the bag and causing a malfunction in that way.

'When the bag has been thus tied by twisting the ends of the tape the forming arm 46 is returned to its solid line position. The length of time that the forming arm 46 remains in its dotted line position before returning to its solid line position as shown in FIG. 1 is controlled by an air flow regulator 86 in the air line 88 for the air cylinder 20. When the forming arm 46 has moved away from its dotted line position, the accuating lever 58 for the air valve 60 will be released thus permitting the spring to pull rearwardly on the chain 64 thus extending the piston rod 62 again to its solid line position as shown in FIG. 2. l

A nut and cap screw arrangement 88 on the forming arm 46 engages an accuating member on the air valve 90 fixed to the plate 10 when the arm 46 returns to its full solid line position as shown in FIG-1. The air valve 90 is connected by suitable hoses such as that shown at 92 to the air cylinder 22. Upon accuation of the air valve 90 the air cylinder 22 will be operated to retract the piston rod 94 into the air cylinder 22. At its forward end piston rod 94 has affixed thereto a flexible chain 96 trained about the sprocket 98. The other end of the chain 96 is fixed to a spring 100 the opposite end of which at 102 is affixed to a suitable portion of the plate frame 10. The sprocket 98 cooperates with a one-way clutch mechanism 104 suitably mounted by means of the bolt 106 to the frame plate 10. The one-way clutch 104 rotates upon retraction of the piston rod 94 and accuates tape feeding roller 108 to rotate the same in a clockwise direction as viewed in FIG. 1. Cooperating with tape feeding roller 108 is an idler roller 110 journaled at 112 on pivoted idler arm 114 which arm 114 is pivoted at 116 to the frame plate 10. A spring 118 between the idler arm 114 and a fixed stop 120 urges the arm 114 about the pivot 116 in a clockwise direction as viewed in FIG. 1. In this way the tape 50 is gripped between the idler roller 110 and the tape feeding roller 108. As stated above, accuation of the air valve 90 will operate air cylinder 22 to retract piston rod 94 (moving toward the right in FIG. 1) thus rotating the sprocket 98 and the one-way clutch 104 to drive the feeding roller 108 in a clockwise direction as viewed in FIG. 1. The tape 50, gripped between the feeding roller 108 and the idler roller 110 is fed forwardly (toward the left in FIG. 1) through the forming arm 46 including through a hole 122 in the knife block 54, across the knife receiving slot 56 and thence through an opening 51 adjacent the throat 48, across the front of the throat 48 and then into the enclosed passage 124 on the outer end of the forming arm 46. ltwill be appreciated that the tape will already be present in the rearward portion of the forming arm 46 in the channel guide or opening 126 since the tape is cut against the knife block 54 and remains present in the opening 126 after its initial threading therethrough. The tape 50, of course, is pulled from a suitable spool 128 thereof mounted rotatably on a shaft. 132 supported from an extension 134 projecting rearwardly from the frame plate 10. A suitable flexible and weighted brake of conventional type may be trained about the spool 128 to prevent override and free wheeling of the spool 128 upon operation of the feeding mechanism. Subsequent to the feeding of the tape through the forming arm 46 the spring 100 operates to pull the chain 96 in a counterclockwise direction about the supporting shaft 106 thus extending the piston rod 94 again. During this extension operation the one-way clutch 104 does not cause the tape feeding roller 108 to move, but rather the chain 96 may move the sprocket 98 without moving the feed roller 108 in either direction.

A suitable source of air under compression may be connected through the connection 136 to the air regulator 138 which in turn is connected through conduit 140 to all of the air operated mechanisms of the device as mentioned above and including an air pilot valve 142 and a manifold 144.

An arm146 extending laterally of the piston rod 94 engages the head 148 of a nut and bolt arrangement 150 threaded in an upstanding member 152 fixed to the plate frame 10. The stop 148 may thus be adjusted to adjust the length of travel of the piston rod 94 and, consequently, the length of tie-tape that is fed uponeach operation of the cylinder 22.

The tie-tape used, of course, may be any strip or ribbon that will maintain a twisted shape such as fine wire either coated or uncoated'or sandwiched in a narrow ribbon of paper or plastic.

I claim:

1. A bag tying machine'for tying with a twistable tietape the open end of a flexible bag, comprising a rotatable tie-tape twister having outwardly extending twister arms; a swingable forming arm having a bag-gathering throat, the throat having a pair of confronting, inwardly-directed lobes defining an entrance, and an interior cavity wider than and communicating with the entrance, the interior cavity receiving the rotating twister arms when the forming arm is swung toward the tietape twister, the entrance to the throat having opposed, confronting guide openings for positioning a predetermined length of tie-tape across the entrance; the thuspositioned tie-tape being contacted by and bent around the open end of a flexible bag passing through the entrance into the cavity, the ends of the bent, predetermined length of tie-tape extending outwardly of the cavity into the respective guide openings at the entrance to positively orient the tie-tape ends with respect to the twister arms rotating within the cavity and to thus assure positive engagement of the twister arms with the tie-tape.

2. The bag tying machine of claim 1 including cut-off means actuated by movement of the forming arm for cutting a tie-tape to length, a portion of the cut-off means being mounted on the forming arm.

3. A bag tying machine for twisting a tie-tape about the open end of a flexible bag and comprising a rotatable tie-tape twister having outwardly extending twister arms, a swingable forming arm having a bag-gathering throat with inwardly directed, confronting lobes defining an entrance communicating with an interior cavity wider than the entrance and dimensioned to receive the outwardly extending rotating twister arms within the cavity when the forming arm is swung toward the tietape twister, the entrance lobes having opposed, confronting guide openings for guidance of a twistable tie-v sure engagement of the twister arms with the tie-tape ends.

4. The bag tying machine of claim 3 wherein the cutting means comprises a stationary cut-off knife, and a cooperating knife block mounted on the arm for movement into contact with the knife to cut the tie-tape to length.

5. The bag tying machine of claim 3 wherein said machine is energized solely by an exterior source of air under pressure. 

1. A bag tying machine for tying with a twistable tie-tape the open end of a flexible bag, comprising a rotatable tie-tape twister having outwardly extending twister arms; a swingable forming arm having a bag-gathering throat, the throat having a pair of confronting, inwardly-directed lobes defining an entrance, and an interior cavity wider than and communicating with the entrance, the interior cavity receiving the rotating twister arms when the forming arm is swung toward the tie-tape twister, the entrance to the throat having opposed, confronting guide openings for positioning a predetermined length of tie-tape across the entrance; the thus-positioned tie-tape being contacted by and bent around the open end of a flexible bag passing through the entrance into the cavity, the ends of the bent, predetermined length of tie-tape extending outwardly of the cavity into the respective guide openings at the entrance to positively orient the tie-tape ends with respect to the twister arms rotating within the cavity and to thus assure positive engagement of the twister arms with the tie-tape.
 2. The bag tying machine of claim 1 including cut-off means actuated by movement of the forming arm for cutting a tie-tape to length, a portion of the cut-off means being mounted on the forming arm.
 3. A bag tying machine for twisting a tie-tape about the open end of a flexible bag and comprising a rotatable tie-tape twister having outwardly extending twister arms, a swingable forming arm having a bag-gathering throat with inwardly directed, confronting lobes defining an entrance communicating with an interior cavity wider than the entrance and dimensioned to receive the outwardly extending rotating twister arms within the cavity when the forming arm is swung toward the tie-tape twister, the entrance lobes having opposed, confronting guide openings for guidance of a twistable tie-tape therethrough across the entrance; means for advancing a length of tie-tape through the guide openings; and means actuated by movement of the forming arm for cutting the tie-tape to a predetermined length, the tie-tape being substantially doubled back upon itself within the cavity with its ends supported by the guide openings when a bag is gathered in the interior cavity of the forming arm, the outwardly extending ends of the predetermined length of tie-tape thus being positively oriented with respect to the twister arms to assure engagement of the twister arms with the tie-tape ends.
 4. The bag tying machine of claim 3 wherein the cutting means comprises a stationary cut-off knife, and a cooperating knife block mounted on the arm for movement into contact with the knife to cut the tie-tape to length.
 5. The bag tying machine of claim 3 wherein said machine is energized solely by an exterior source of air under pressure. 